摘要
以聚酯多元醇和异佛尔酮二异氰酸酯 (IPDI)为主要原料 ,引入亲水单体二羟甲基丙酸 (DMPA) ,按不同配比合成了系列聚氨酯乳液。考察了硬段含量对乳液粒径、表观黏度、膜吸水性、硬度、力学性能的影响 ,并通过动态力学性能测试 (DMA)研究了软段和硬段的玻璃化转变温度。结果表明 :提高—NCO/—OH物质的量之比、DMPA用量均使聚氨酯中软段的玻璃化温度Tg(s)降低 ,硬段的玻璃化温度Tg(h)升高 ,ΔT值增加 ,软硬段相分离程度增加。随乙二胺用量的增加 ,会使软段玻璃化转变温度Tg(s)移向高温 ,软硬段相分离程度降低 ;硬段含量提高 ,胶膜硬度增加 ,拉伸强度增加 ,胶膜耐水性降低。
A range of polyurethane emulsions has been prepared based on polyester polyol and IPDI as main raw materials, incorporated with hydrophilic monomer DMPA to prepare different formulas. The influence of content of hard segmer on particle size of emulsion, apparent viscosity, moisture absorption of film, hardness and mechanical properties is discussed. The T g of hard and soft segmer is analyzed through DMA. The result indicates that an increase of mol ratio of —NCO/—OH and loading of DMPA can reduce the T g of polyurethane soft segmer, increase the T g of polyurethane hard segmer, increase ΔT value, and reduce the phase separation of soft and hard segmers. An increase of the content of hard segmer will increase film hardness and elongation strength, and lower water resistance.
出处
《涂料工业》
CAS
CSCD
2004年第8期5-10,共6页
Paint & Coatings Industry
